Editing Arthritis (section)

== Diagnosis ==
{{Synovial fluid analysis}}
[[File:Osteoarthritis in the left hand index finger.jpg|thumb|right|Osteoarthritis in the left hand index finger of a 63-year-old woman]]

Diagnosis is made by clinical examination from an appropriate health professional, and may be supported by tests such as radiologic imaging and blood tests, depending on the type of suspected arthritis.<ref>{{cite web|title = How is arthritis diagnosed? {{!}} Arthritis Research UK|url = http://www.arthritisresearchuk.org/arthritis-information/conditions/arthritis/diagnosis.aspx|website = www.arthritisresearchuk.org|access-date = 9 June 2015|url-status = live|archive-url = https://web.archive.org/web/20150402061641/http://www.arthritisresearchuk.org/arthritis-information/conditions/arthritis/diagnosis.aspx|archive-date = 2 April 2015}}</ref> Pain patterns may vary depending on the type of arthritis and the location. [[Rheumatoid arthritis]] is generally worse in the morning and associated with stiffness lasting over 30 minutes.<ref name=":5">{{cite web|url=https://www.niams.nih.gov/health-topics/rheumatoid-arthritis|title=Rheumatoid Arthritis| vauthors = Garrick N |date=20 April 2017|website=National Institute of Arthritis and Musculoskeletal and Skin Diseases|access-date=6 May 2019}}</ref> On the other hand, with osteoarthritis, the pain tends to initially be related to activity and then becomes more constant over time.<ref>{{Cite journal |last1=Yu |first1=Huan |last2=Huang |first2=Tianwen |last3=Lu |first3=William Weijia |last4=Tong |first4=Liping |last5=Chen |first5=Di |date=2022-04-22 |title=Osteoarthritis Pain |journal=International Journal of Molecular Sciences |volume=23 |issue=9 |pages=4642 |doi=10.3390/ijms23094642 |doi-access=free |issn=1422-0067 |pmc=9105801 |pmid=35563035}}</ref>

Important features to look out for include the following:

* Rate of onset of symptoms
* Pattern of joint involvement
* Symmetry of symptoms
* Early morning stiffness
* Associated tenderness around the joint
* Locking of joint with inactivity
* Aggravating and relieving factors, and/or
* Presence of systemic symptoms

Physical examination may include observing the affected joints, evaluating gait, and examining the skin for findings that could be related to rheumatological disease or pulmonary inflammation. Physical examination may confirm the diagnosis or may indicate systemic disease. Chest radiographs are often used to follow progression or help assess severity.<ref name="davis">{{cite journal |last1=Davis |first1=J. Lucian |last2=Murray |first2=John F. |date=2016 |title=History and Physical Examination |journal=Murray and Nadel's Textbook of Respiratory Medicine |pages=263–277.e2 |doi=10.1016/B978-1-4557-3383-5.00016-6 |pmc=7152492|isbn=978-1-4557-3383-5 }}</ref>

Screening blood tests for suspected arthritis include: [[rheumatoid factor]], [[antinuclear factor]] (ANF), [[extractable nuclear antigen]], and specific antibodies.<ref name=davis/>

Rheumatoid arthritis patients often have elevated erythrocyte sedimentation rate (ESR, also known as sed rate) or C-reactive protein (CRP) levels, which indicates the presence of an inflammatory process in the body.<ref name=":5" /> Anti-cyclic citrullinated peptide (anti-CCP) antibodies and rheumatoid factor (RF) are two more common blood tests when assessing for rheumatoid arthritis.<ref name=":5" />

Imaging tests like X-rays are commonly utilized to diagnose and monitor arthritis.<ref name=":2" /> Other imaging tests for rheumatoid arthritis that may be considered include computed tomography (CT) scanning, positron emission tomography (PET) scanning, bone scanning, and dual-energy X-ray absorptiometry (DEXA).<ref name=":2">{{cite web |title=Rheumatoid arthritis - Diagnosis |url=https://www.nhs.uk/conditions/rheumatoid-arthritis/diagnosis/ |website=nhs.uk |language=en |date=23 October 2017}}</ref>

=== Osteoarthritis ===
{{Main|Osteoarthritis}}
[[File:Varus Knee Osteoarthritis Xray.jpg|thumb|Bilateral medial joint space narrowing with osteophytes in varus knees with osteoarthritis]]

[[Osteoarthritis]] (OA) is the most common form of arthritis.<ref name=Van2010>{{cite journal | vauthors = VanItallie TB | title = Gout: epitome of painful arthritis | journal = Metabolism | volume = 59 | issue = Suppl 1 | pages = S32–S36 | date = October 2010 | pmid = 20837191 | doi = 10.1016/j.metabol.2010.07.009 }}</ref> It affects humans and other animals, notably dogs, but also occurs in cats and horses. It can affect both the larger (i.e. knee, hip, shoulder, etc.) and the smaller joints (i.e. fingers, toes, foot, etc.) of the body. The disease is caused by daily wear and tear of the joint. This process can progress more rapidly as a result of injury to the joint. Osteoarthritis is caused by the break down of the smooth surface between two bones, known as cartilage, which can eventually lead to the two opposing bones coming in direct contact and eroding one another. OA symptoms typically begin with minor pain during physical activity, but can eventually progress to be present at rest. The pain can be debilitating and prevent one from doing activities that they would normally do as part of their daily routine. OA typically affects the weight-bearing joints, such as the back, knee and hip due to the mechanical nature of this disease process. Unlike rheumatoid arthritis, osteoarthritis is most commonly a disease of the elderly. The strongest predictor of osteoarthritis is increased age, likely due to the declining ability of [[chondrocytes]] to maintain the structural integrity of cartilage.<ref>{{cite journal | vauthors = Pereira D, Ramos E, Branco J | title = Osteoarthritis | journal = Acta Médica Portuguesa | volume = 28 | issue = 1 | pages = 99–106 | date = January 2015 | pmid = 25817486 | doi = 10.20344/amp.5477 | doi-access = free }}</ref> More than 30 percent of women have some degree of osteoarthritis by age 65. One of the primary tools for diagnosing OA are X-rays of the joint. Findings on X-ray that are consistent with OA include those with joint space narrowing (due to cartilage breakdown), bone spurs, sclerosis, and bone cysts.<ref>{{Cite journal |last1=Fan |first1=Zijuan |last2=Yan |first2=Lei |last3=Liu |first3=Haifeng |last4=Li |first4=Xiaoke |last5=Fan |first5=Kenan |last6=Liu |first6=Qiang |last7=Li |first7=Jiao Jiao |last8=Wang |first8=Bin |date=2023-03-29 |title=The prevalence of hip osteoarthritis: a systematic review and meta-analysis |journal=Arthritis Research & Therapy |language=en |volume=25 |issue=1 |page=51 |doi=10.1186/s13075-023-03033-7 |doi-access=free |issn=1478-6362 |pmc=10053484 |pmid=36991481}}</ref>

=== Rheumatoid arthritis ===
{{Main|Rheumatoid arthritis}}
[[File:X-ray of right fourth PIP joint with bone erosions by rheumatoid arthritis.jpg|thumb|[[Bone erosion]]s by [[rheumatoid arthritis]]<ref>{{cite journal | vauthors = Ideguchi H, Ohno S, Hattori H, Senuma A, Ishigatsubo Y | title = Bone erosions in rheumatoid arthritis can be repaired through reduction in disease activity with conventional disease-modifying antirheumatic drugs | journal = Arthritis Research & Therapy | volume = 8 | issue = 3 | pages = R76 | year = 2006 | pmid = 16646983 | pmc = 1526642 | doi = 10.1186/ar1943 | doi-access = free }}</ref>]]

[[Rheumatoid arthritis]] (RA) is a disorder in which the body's own immune system starts to attack body [[tissue (biology)|tissues]] specifically the cartilage at the end of bones known as articular cartilage.<ref name="niams-ra">{{cite web|url=https://www.niams.nih.gov/health-topics/rheumatoid-arthritis |title=Rheumatoid arthritis|date=November 2022|access-date=30 January 2025|publisher=National Institute of Arthritis and Musculoskeletal and Skin Diseases, US National Institutes of Health}}</ref> The attack is not only directed at the joint but to many other parts of the body. RA often affects joints in the fingers, wrists, knees and elbows, is symmetrical (appears on both sides of the body), and can lead to severe progressive [[deformity]] in a matter of years if not adequately treated. RA usually onsets earlier in life than OA and commonly effects people aged 20 and above. In children, the disorder can present with a skin [[rash]], [[fever]], [[pain]], disability, and limitations in daily activities.<ref name=niams-ra/> With earlier diagnosis and appropriate aggressive treatment, many individuals can obtain control of their symptoms leading to a better quality of life compared to those without treatment.<ref name=niams-ra/><ref>{{cite report |url=https://effectivehealthcare.ahrq.gov/topics/rheumatoid-arthritis-medicine-update/final-report-update-2018 |title=Drug Therapy for Early Rheumatoid Arthritis: A Systematic Review Update |last1=Donahue |first1=Katrina E. |last2=Gartlehner |first2=Gerald |date=2018 |publisher=Agency for Healthcare Research and Quality (AHRQ) |doi=10.23970/ahrqepccer211 |last3=Schulman |first3=Elizabeth R. |last4=Jonas |first4=Beth |last5=Coker-Schwimmer |first5=Emmanuel |last6=Patel |first6=Sheila V. |last7=Weber |first7=Rachel Palmieri |last8=Lohr |first8=Kathleen N. |last9=Bann |first9=Carla|doi-access=free }}</ref>

One of the main triggers of bone erosion in the joints in rheumatoid arthritis is inflammation of the [[synovium]] (lining of the joint capsule), caused in part by the production of pro-inflammatory [[cytokine]]s and receptor activator of nuclear factor kappa B ligand (RANKL), a cell surface protein present in Th17 cells and osteoblasts.<ref name="Chabaud_2000">{{cite journal | vauthors = Chabaud M, Garnero P, Dayer JM, Guerne PA, Fossiez F, Miossec P | title = Contribution of interleukin 17 to synovium matrix destruction in rheumatoid arthritis | journal = Cytokine | volume = 12 | issue = 7 | pages = 1092–1099 | date = July 2000 | pmid = 10880256 | doi = 10.1006/cyto.2000.0681 }}</ref> Osteoclast activity can be directly induced by osteoblasts through the RANK/RANKL mechanism.<ref name="pmid21464945">{{cite journal | vauthors = Won HY, Lee JA, Park ZS, Song JS, Kim HY, Jang SM, Yoo SE, Rhee Y, Hwang ES, Bae MA | display-authors = 6 | title = Prominent bone loss mediated by RANKL and IL-17 produced by CD4+ T cells in TallyHo/JngJ mice | journal = PLOS ONE | volume = 6 | issue = 3 | pages = e18168 | date = March 2011 | pmid = 21464945 | pmc = 3064589 | doi = 10.1371/journal.pone.0018168 | bibcode = 2011PLoSO...618168W | doi-access = free }}</ref>
[[File:Lupusfoto.jpg|thumb|160x160px|This is a malar ("butterfly") skin rash that is commonly seen in patients with Lupus.]]

=== Lupus ===
{{Main|Lupus erythematosus}}

[[Lupus erythematosus|Lupus]] is an autoimmune [[collagen]] [[Blood vessel|vascular]] disorder that can be present with severe arthritis. In fact, about 90% of patients with Lupus have musculoskeletal involvement.<ref name=":6">{{Cite journal |last1=Ceccarelli |first1=Fulvia |last2=Govoni |first2=Marcello |last3=Piga |first3=Matteo |last4=Cassone |first4=Giulia |last5=Cantatore |first5=Francesco Paolo |last6=Olivieri |first6=Giulio |last7=Cauli |first7=Alberto |last8=Favalli |first8=Ennio Giulio |last9=Atzeni |first9=Fabiola |last10=Gremese |first10=Elisa |last11=Iannone |first11=Florenzo |last12=Caporali |first12=Roberto |last13=Sebastiani |first13=Marco |last14=Ferraccioli |first14=Gian Franco |last15=Lapadula |first15=Giovanni |date=2022-10-12 |title=Arthritis in Systemic Lupus Erythematosus: From 2022 International GISEA/OEG Symposium |journal=Journal of Clinical Medicine |language=en |volume=11 |issue=20 |pages=6016 |doi=10.3390/jcm11206016 |doi-access=free |issn=2077-0383 |pmc=9604412 |pmid=36294337}}</ref> Symptoms in these patients can often mimic those of rheumatoid arthritis with similar stiffness and pain patterns. Joints in the fingers, wrist, and knee tend to be the most affected.<ref name=":6" /> Other features commonly seen in patients with Lupus include a skin rash (pictured on the right), extreme [[photosensitivity]], [[baldness|hair loss]], [[kidney]] problems, and shortness of breath secondary to scarring that occurs in the lungs.<ref>{{EMedicine|article|331715|Rheumatoid Arthritis: Differential Diagnoses & Workup|diagnosis}}</ref>

=== Gout ===
{{Main|Gout}}
[[File:Gout Signs and Symptoms.jpg|thumb|Gout most commonly affects the big toe, leading to swelling, redness, and warmth around that area.]]

In the early stages of gout, usually only one joint is affected; however over time, many joints can become affected. Gout most commonly occurs in joints located in the big toe, knee, and/or fingers.<ref name=mayo-gout/> During a gout flare, the affected joints often become swollen with associated warmth and redness. The resulting pain can be significant and potentially debilitating.<ref name="Becker">{{cite book |title=Arthritis and Allied Conditions: A textbook of Rheumatology edition 15 |vauthors=Becker MA |publisher=Lippincott Williams & Wilkins |year=2005 |pages=2303–2339}}</ref> When one of these flares occurs, management involves the use of anti-inflammatories, such as NSAIDs, colchicine, or glucocorticoids.<ref name=":8">{{Cite journal |last1=Afinogenova |first1=Yuliya |last2=Danve |first2=Abhijeet |last3=Neogi |first3=Tuhina |date=2022-03-01 |title=Update on Gout Management: what's old and what's new |journal=Current Opinion in Rheumatology |volume=34 |issue=2 |pages=118–124 |doi=10.1097/BOR.0000000000000861 |issn=1040-8711 |pmc=8799507 |pmid=34907116}}</ref> In between gout flares, it is recommended that patients take medications that decrease the production of uric acid (i.e. allopurinol, febuxostat) or increase the elimination of uric acid from the body (i.e. probenecid).<ref name=":8" /><ref name="Ali">{{cite journal |vauthors=Ali S, Lally EV |date=November 2009 |title=Treatment failure gout |journal=Medicine and Health, Rhode Island |volume=92 |issue=11 |pages=369–371 |citeseerx=10.1.1.608.3812 |pmid=19999896}}</ref>

Gout has been associated with excessive intake of alcohol and food, such as red meat.<ref name=mayo-gout/> Thus, it is also recommended that patients with gout adhere to a diet rich in fiber, vegetables, and whole grains, while limiting the intake of alcohol and fatty foods.<ref name=mayo-gout/>

There is also an uncommon form of gout that is known as [[Calcium pyrophosphate deposition disease|pseudogout]], which is caused by the formation of calcium pyrophosphate crystals in the joint.<ref name=":9">{{Cite journal |last1=Stack |first1=John |last2=McCarthy |first2=Geraldine |date=2021-12-01 |title=Calcium pyrophosphate deposition (CPPD) disease – Treatment options |journal=Best Practice & Research Clinical Rheumatology |series=Crystal Induced Arthritis |volume=35 |issue=4 |pages=101720 |doi=10.1016/j.berh.2021.101720 |pmid=34756508 |issn=1521-6942|doi-access=free }}</ref> Unlike gout, no targeted treatments are currently available.<ref name=":9" /> At this time, management is aimed at decreasing inflammation in order to reduce the intensity and frequency of flares.<ref name=":9" />

=== Comparison of types ===
{|class="wikitable"
|+ Comparison of some major forms of arthritis<ref name=agabegi2nd6-7unless>Unless otherwise specified in table box, the reference is: {{cite book | vauthors = Agabegi ED, Agabegi SS |chapter=Table 6–7 |title=Step-Up to Medicine |url=https://archive.org/details/stepuptomedicine0000agab |url-access=registration |series=Step-Up Series |publisher=Lippincott Williams & Wilkins |location=Hagerstwon MD |year=2008 |page=[https://archive.org/details/stepuptomedicine0000agab/page/253 253] |isbn=978-0-7817-7153-5 }}</ref>
|-
!  !! [[Osteoarthritis]] !! [[Rheumatoid arthritis]] !! [[Gouty arthritis]]
|-
! Speed of onset
| Months-Years || Weeks-months<ref name=Chan1994>[[Diagnosis lag time]] of median 4 weeks, and median [[diagnosis lag time]] of 18 weeks, taken from: {{cite journal | vauthors = Chan KW, Felson DT, Yood RA, Walker AM | title = The lag time between onset of symptoms and diagnosis of rheumatoid arthritis | journal = Arthritis and Rheumatism | volume = 37 | issue = 6 | pages = 814–820 | date = June 1994 | pmid = 8003053 | doi = 10.1002/art.1780370606 }}</ref> || Hours for an attack<ref name=Harwood-Nuss2009>{{cite book | vauthors = Schaider J, Wolfson AB, Hendey GW, Ling L, Rosen CL |title=Harwood-Nuss' Clinical Practice of Emergency Medicine (Clinical Practice of Emergency Medicine (Harwood-Nuss)) |publisher=Lippincott Williams & Wilkins |location=Hagerstwon, MD |year=2009 |pages=740 (upper right of page) |isbn=978-0-7817-8943-1 |url=https://books.google.com/books?id=Idb0Z658lFQC&pg=PT773 |url-status = live|archive-url=https://web.archive.org/web/20150321185321/http://books.google.com/books?id=Idb0Z658lFQC&pg=PT773 |archive-date=21 March 2015 }}</ref>
|-
! Main locations
| Weight-bearing joints (such as [[knee]]s, [[Hip#Articulation|hips]], [[vertebral column]]) and hands
| Hands ([[Proximal interphalangeal joint|proximal interphalangeal]] and [[metacarpophalangeal joint]]) [[wrist]]s, [[ankle]]s, [[knee]]s and [[hip]]s
| [[Great toe]], [[ankle]]s, [[knee]]s and [[elbow]]s
|-
! Inflammation
| May occur, though often mild compared to inflammation in rheumatoid arthritis || Yes || Yes
|-
! [[Radiologic]] changes
|
* Narrowed joint space
* [[Osteophyte]]s
* Local [[osteosclerosis]]
* [[Subchondral cyst]]s
|
* Narrowed joint space
* Bone erosions
|
* "Punched out" bone erosions
|-
! Laboratory findings
| None || [[Anemia]], elevated [[erythrocyte sedimentation rate|ESR]] and [[C-reactive protein]] (CRP), [[rheumatoid factor]], [[anti-citrullinated protein antibody]]
| [[Crystal]] in joints
|-
!Other features
|
* No systemic signs
* [[Bouchard's nodes|Bouchard's]] and [[Heberden's node]]s
|
* [[#Signs and symptoms|Extra-articular features]] are common
* [[Ulnar deviation]], [[swan neck deformity|swan neck-]] and [[Boutonniere deformity]] of the hand
|
* [[Tophus|Tophi]]
* [[Nephrolithiasis]]
|}

=== Other ===
[[Infectious arthritis]] is another severe form of arthritis that is sometimes referred to as septic arthritis. It typically occurs when a patient is ill or has an infection. Common symptoms include the sudden onset of chills, fever, and joint pain. The condition is caused by bacteria that spread through the blood stream from elsewhere in the body. This bacteria can travel to specific joints and start to erode cartilage. Infectious arthritis must be rapidly diagnosed and treated promptly in order to prevent irreversible joint damage.<ref>{{cite web | url = http://www.arthritis.org/ | title = Severe Arthritis Disease Facts | archive-url = https://web.archive.org/web/20070423120449/http://www.arthritis.org/ | work = Arthritis.org | archive-date=23 April 2007 | access-date = 5 February 2010 }}</ref> Only about 1% of cases of infectious arthritis are a result of [[virus]]es.<ref name="pmid27037381">{{cite journal | vauthors = Marks M, Marks JL | title = Viral arthritis | journal = Clinical Medicine | volume = 16 | issue=2 | pages = 129–134 | date=2016 | doi = 10.7861/clinmedicine.16-2-129 | pmc=4868140 | pmid = 27037381}}</ref> Within recent years, the virus [[SARS-CoV-2]], which causes [[Covid-19]], has been added to this list.<ref name="pmid35655110">{{cite journal | vauthors = Slouma M, Abbes M, Louzir B | title = Reactive arthritis occurring after COVID-19 infection: a narrative review | journal = [[Infection (journal)|Infection]] | volume = 51 | issue=1 | pages = 37–45 | date=2023 | doi = 10.1007/s15010-022-01858-z | pmc=9162104 | pmid = 35655110}}</ref> SARS-CoV-2 tends to cause [[reactive arthritis]] rather than local septic arthritis.<ref name="pmid35655110" />

[[Psoriasis]] can develop into psoriatic arthritis.<ref name=":3" /> With psoriatic arthritis, most individuals first develop skin symptoms (such as scaly patches and itchiness) and then begin to experience joint related symptoms. They typically experience continuous joint pain, stiffness and swelling like other forms of arthritis. This disease can go into [[remission (medicine)|remission]], but there is currently no known cure for the disorder.<ref name=":3" /> Treatment current revolves around decreasing autoimmune attacks with immune suppressive medications.<ref name=":3" /> A small percentage of patients with psoriatic arthritis can develop a severely painful and destructive form of arthritis which destroys the small joints in the hands and sometimes lead to permanent disability and loss of hand function.<ref name=":3">{{cite web | url = http://www.mayoclinic.com/health/psoriatic-arthritis/DS00476/DSECTION=symptoms | title = Psoriatic Arthritis | work = Mayo Clinic | archive-url = https://web.archive.org/web/20100209073725/http://www.mayoclinic.com/health/psoriatic-arthritis/DS00476/DSECTION%3Dsymptoms | archive-date=9 February 2010 | access-date = 5 February 2010 }}</ref>